Modern data centers house large numbers of computer servers, typically housed in rows of server cabinets, in which a plurality of servers are mounted in a closely spaced relation within the cabinets. In operation, the densely arranged servers generate substantial heat, which must be removed in order to prevent overheating and malfunction of the equipment. The individual server units generally are provided with internal fans, which pull cooling air through the unit. However, because of the high density of the equipment, it is customary to provide substantial air conditioning systems to supply cooled air to the fronts of the cabinets, available to be drawn through the individual servers by their internal fans.
Operating efficiency of the cooling systems has become an increasing problem as the power output of the servers has been progressively increased and the expense of cooling them has become very meaningful. A significant aspect of controlling cooling costs is the prevention or minimization of mixing of the cooled air at the front of the cabinet, with warm air in the data center. Where mixing is allowed to occur outside of the servers, the capacity of the A/C equipment must be enlarged, at increased capital expense. In addition the efficiency of the A/C equipment is compromised due to the lower temperature differential between the air returned to the A/C equipment.
Among the techniques employed at modern data centers to improve efficiency is arranging rows of server cabinets in hot- and cold-air aisles. Typically, two rows of server cabinets are oriented back-to-back, with cool air being supplied to the fronts of the rows (forming cold aisles) and warm air being collected in the hot aisle between the two rows, which is then returned to the A/C unit. This technique represents an improvement over previous arrangements but still permits considerable quantities of the cool air to bypass the servers and mix with warm air.
Other techniques employed in modern data centers are complete air containment (i.e., complete enclosure) and partial air containment. Complete air containment involves completely closing off an aisle, for example a cold-air aisle, between rows of server cabinets. In complete air containment, roof baffles are connected between the top portions of adjacent rows of server cabinets, to create an upper barrier, and doors (or walls) are connected between side potions of the cabinets at the ends of adjacent rows, to create side barriers. The floor of the server room and the cabinets provide the remaining sides of the complete enclosure. In a cold-air aisle, for example, perforations in the floor panels allow air to flow into the enclosed cold-air aisle and then to the servers.
In partial air containment systems, the system does not completely enclose the area between adjacent rows of cabinets. The purpose and intention of partial air containment systems is to inhibit undesirable airflow, but at the same time provide benefits of an open aisle configuration.